When particle ID is included as part of the scalar input, we follow the “experimentally plausible” labeling scheme of [1]}, where particles are categorized into one of eight types: photons, neutral hadrons, and positively- and negatively-charged muons, electrons, and hadrons.
These labels are input to the network via a trainable 3-dimensional embedding layer, which are concatenated with the particle's \(p_\mathrm {T}\)  and passed as a triplet into the \(Z_c\)  network.
